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Some Grassland Facts
Compiled by: John McAllister,
Mpumalanga Parks Board General Characteristics
· The climate typically consists of warm,
wet summers followed by cold, dry winters with heavy frosts. · Vegetation is dominated by grass
species with many bulbous plants. · Shrubs and trees are restricted by fire
and frost to protected kloofs and rocky areas · The topography is characterised by
rolling hills and valleys. · They are generally found at either high
altitudes or high latitudes. · They are often characterised by the
presence of many wetlands. Origins
· Classical authors (e.g.
Acocks, Edwards, Galpin, Huntley, Killick, Mentis, Philips, Roux and Tainton) consider the
South African Grassland Biome to be artificially maintained by anthropogenically caused
fires and that it is seral to the Forest, Fynbos or Savanna Biomes. · Modern authors (e.g.
Komarek, Manry & Knight, Matthews et al,
Moll, Rutherford & Westfall and Sunquist) consider that lightning initiated fires,
together with dry, frosty winters are the root cause of grasslands. Forests and savannas have and still are invading
the African grasslands. · While the South African Grassland Biome
is now unique in Africa grasslands once used to cover nearly 50% of Africas surface. A change in climate, around 3 million years ago
allowed trees to encroach into these grasslands and create the savannas we know today. This climatic change may also have allowed man,
then largely frugivorous, to leave the forests and jungles to settle in the savannas. Even today the vast majority of the African
Savanna Biomes wealth of large herbivorous mammals are grazers not browsers. · Prof. Van Wyk of the University of
Pretoria believes that South African grasslands have an ancient origin. Most plant reproduction takes place vegetatively
and not through seed production, particularly among bulbous plants and climax grasses. One of the implications of this is that many
grass clumps are genetically identical to grass clumps that were in the area as much as 2
000 years ago, ie. they are to all intents and purposes the same individuals (A E van Wyk,
Pers. Comm. 1994). Water Supply
· Montane grasslands and fynbos are the
great collectors of rain water in South Africa.
They reduce immediate runoff and thus erosion, hold the water as ground
water or in wetlands and release it slowly throughout the year (including the dry season)
through seepage zones, etc. - a sort of sponge effect. · The southern montane grasslands of
Mpumalanga, for example, provide a year-round water supply essential for the cooling of
the power generators of the Highveld power stations (Department of Water Affairs, 1986) -
power stations that produce 70% of South Africas electricity requirements. Without this water the coal fields of Mpumalanga
would be unable to generate this power. Species Diversity
Plants
· Botanically grasslands support 81
species per 1 000 mē. This compares to 86
species in the Renosterveld and 65 in the fynbos (Huntley, 1989). · Of every six plants found in pristine
South African Grasslands only one is a grass (A E van Wyk, Pers. comm. 1994) · There are more than 100 endemic plant
species in the Mpumalanga grasslands alone (Duthie, 1992). · More than 50% of the plants listed as
threatened in the erstwhile Transvaal and 43% in KwaZulu-Natal are located in the moist
areas of the Grassland Biome (Duthie, 1992). Birds
· Of the 40 species endemic to South
Africa 21, or 53%, are found in the Grassland Biome.
Twelve (57%) of these are endemic to
the biome. · The southern highland grasslands of
Mpumalanga, together with the adjacent areas of KwaZulu-Natal and the Free State have been
declared an Endemic Bird Area (EBA) in urgent need of conservation by BirdLife
International, advisors to the IUCN on matters affecting birds. An EBA supports at least two endemic species of
birds with a distribution range of less than 50 000 kmē.
The South African Grassland EBA supports three - Rudds Lark, Bothas
Lark and Yellowbreasted Pipit - all considered threatened on a global scale
(Stattersfield, et al, 1998). · Of the 16 species occurring in South
Africa and considered to be threatened on a global scale by BirdLife International 11
(69%) are either entirely restricted to the Grassland Biome or have a substantial
proportion of their local population reliant on this biome.
This is also true for 9 of the 30 near-threatened species (Collar, et al, 1994). · Of the 79 species considered to be
threatened or near threatened on a southern African scale by the Avian Demography Unit
(Barnes, 1996) 31 (39%) are restricted to or substantially dependent on these grasslands. Reptiles and amphibia
· Of the 93 species of threatened
reptiles and amphibians in South Africa 13 (14%) occur in the Grassland Biome (Branch,
1988a) and 11 (85%) of these are endemic to the
biome. · Of the 195 reptiles endemic to South
Africa 42 (22%) are found in the Grassland Biome (Branch, 1988b). Of these 20 (48%) species and a further 7
subspecies are endemic to the biome. · Of the 54 amphibians endemic to South
Africa 16 (30%) are found in the Grassland Biome (Passmore & Carruthers, 1995). Of
these 8 species (50%) are endemic to the biome. Butterflies
· Of the 102 threatened butterflies in
South Africa 31 (30%) occur in the Grassland Biome (Henning & Henning, 1989). One of these species is already extinct and 29
(94%) are endemic to the biome. Mammals
· 15 of the 34 mammals (44%) endemic to
South Africa can be found in the Grassland Biome and 4 of these (27%) are endemic to the biome (Smithers, 1983). · Of the 92 threatened land mammals in
South Africa 18 (20%) can be found in the Grassland Biome. Economics
· The remaining grasslands of Mpumalanga
and KwaZulu-Natal alone provide natural grazing to sheep producing more than 8 million kg
wool annually with a value exceeding R 52 million in 1995. · With large number of endemic species
South Africas grasslands have a high, but as yet virtually untapped eco-tourism
potential worth possibly as much as R 60 million annually. · Although not properly assessed the
economic value of the South African grasslands to a sustainably based traditional medicine
industry must be considerable. · South Africas entire maize crop
and a large proportion of its wheat crop is produced in the Grassland Biome. · By far the largest proportion of South
Africas commercial timber is grown and processed within the biome. · The great bulk of South Africas
mineral wealth lies under the surface of the Grassland Biome. · Water runoff from Mpumalangas
southern highland grassland catchments alone supplies all the water used for cooling
purposes in the Highveld Power Stations and SASOLs Secunda petrol-from-coal plant. Conservation Status
· Between 60 and 80% of South Africas
grassland Veld Types (Acocks, 1975) have been irreversibly transformed (MacDonald, 1989). · Less than 2% of South Africas
grasslands are formally conserved (Rutherford & Westfall, 1986). · Of the 115 859 kmē of grasslands in
the erstwhile Transvaal: * 56 782 kmē was under cultivation by
1987 (MacDonald, 1989); * more than 7 000 kmē was under
plantations by the early 1990s (Cowling & Olivier) and a further 5 000 kmē is
scheduled for tree planting by 2020 (van der Zel, 1989); * South Africas major metropolitan
area - the Gauteng Province - with an area of 30 336 kmē and 8,791 million inhabitants
(Development Bank of South Africa, 1991) - lies almost completely within the area; * 2 000 kmē of the Mpumalanga Highveld
is taken up by South Africas major gold and coal deposits, much of which are mined
in opencast pits (Huntley, et al, 1989). · Pollution levels on the Mpumalanga
Highveld area among the highest in the world
(Huntley, et al, 1989) largely as a result of: * 8 Eskom Power Stations producing 70% of South Africas
power requirements (Huntley, 1989); * 6 pulp and paper mills (a further 8
have been proposed within the biome as a whole) (van der Zel, 1989); * 2 petrol-from-coal plants; * many large industries with a high
potential for causing major pollution disasters (e.g. A multitude of steel, gold chrome
and other metallurgical processing industries). References and Suggested Reading
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1975. Veld Types of South
Africa. Memoirs of the
Botanical Survey of South Africa. Botanical
Research Institute, Department of Agricultural Technical Services. 40:1-128. Barnes K. 1996. Important Bird Areas in South Africa - Guidelines
to Contributors. Unpublished. Branch W R (ed).
1988a. South African Red Data
Book - Reptiles and Amphibians. South African
National Scientific Programmes Report No. 151.
CSIR. Pretoria. 235 pp. Branch W R (ed).
1988b. Field Guide to
the Snakes and Other Reptiles of Southern Africa.
Struik Publishers. Cape Town. 328 pp. Brooke R K. 1984. South African Red Data Book - Birds. South African National Scientific Programmes Report No.
97. CSIR, Pretoria. 213 pp. Collar N J, M J Crosby, and A J
Stattersfield. 1994. Birds to watch 2
: the world list of threatened birds. BirdLife
International. Cambridge, England. 407 pp. Cowling R M and N J J Olivier.
1992. Indigenous plants. In: Fuggle R A and Rabie (eds.). Environmental Management in South Africa. Juta & Co Ltd.
Cape Town. 212-249. Department of Water Affairs.
1986. Management of
the Water Resources of the Republic of South Africa. Government Printer.
Pretoria. 483 pp. Development Bank of South Africa.
1991. 1990/91 Annual
Report. Duthie A. 1992. Wood for the trees.
Bushcall. Jume:6-7. Edwards D. 1967. A plant ecological survey of the Tugela River
Basin. Memoirs of the
Botanical Survey of South Africa. Botanical
Research Institute, Department of Agricultural Technical Services. 36:1-285 Galpin E E. 1926. Botanical Survey of the Springbok Flats. Memoirs of the
Botanical Survey of South Africa. Advisory
Committee for the Botanical Survey of South Africa. Cape
Times Ltd. Cape Town. 12:1-100. Henning S F and G A Henning.
1989. South African Red Data
Book - Butterflies. South African National Scientific Programmes Report No
158. CSIR, Pretoria. 175 pp. Huntley B J.
1984. Characteristics of South
African Biomes. In : Booysen P de V and
Tainton (eds.). Ecological
effects of fire in South African Ecosystems.
Ecological Studies 48. Springer-Verlag. Berlin. 1-17. Huntley B J. (ed.).
1989. Biotic Diversity
in Southern Africa - Concepts and Conservation.
Oxford University Press. Cape
Town. 136-147. Huntley B J, R Siegfried and C Sunter. 1989. South African
Environments into the 21st Century.
Human and Rousseau, Tafelberg. Cape
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1992. Putting
Biodiversity on the Map : Priority Areas for Global Conservation. International
Council for Bird Preservation. Cambridge. United Kingdom.
90 pp. Killick D J B.
1963. An Account of the Plant
Ecology of the Cathedral Peak area of the Drakensberg.
Memoirs of the Botanical Survey of South Africa. Botanical Research Institute, Department
of Agricultural Technical Services. 34:1-178. Komarek E V.
1971. Lightning and Fire
Ecology in Africa. Proceedings of
the Tall Timbers Fire Ecology Conference. 11:473-511. MacDonald I A W.
1989. Mans role in
changing the face of Southern Africa. In :
Huntley B J. (ed.). Biotic Diversity
in Southern Africa - Concepts and Conservation.
Oxford University Press. Cape
Town. 51-77. Manry D E and R S Knight.
1986. Lightning Density and
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Bredenkamp. 1993. Endemic
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55 pp. Mentis M T and B J Huntley.
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Grassland Biome Project. . South African
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Scotcher. 1974. Veld
burning in Giants Castle Game Reserve, Natal Drakensberg. Proceedings of the Grassland Society of Southern
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Grassland Biome - a Heritage Lost? Veld and Flora. 72(4):128-129. Passmore N I & V C Carruthers.
1995. South African
Frogs - a Complete Guide. Southern
Book Publishers and Witwatersrand University Press.
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at Groenkloof. Second Report. Science Bulletin 17. Department of Agriculture. Union of South Africa. 17 pp. Roux E.
1969. Grass, a Story
of Frankenwald. Oxford University
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212 pp. Rutherford M C and R H Westfall.
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- an Objective Categorisation. Memoirs of the Botanical Survey of South Africa. Botanical Research Institute, Department
of Agricultural and Water Supply. Pretoria. 54:1-98. Smithers R H N.
1983. The mammals of
the Southern African Subregion. University
of Pretoria, Pretoria. 736 pp. Smithers R H N.
1986. South African Red Data Book - Terrestrial Mammals. South African National Scientific Programmes Report No
125. CSIR, Pretoria. 216 pp. Sunquist F. 1986. Peering into the secrets of Grasslands. International Wildlife. 16(2):52-58. Stattersfield, A. J., Crosby, M. J., Long, A. J. and Wege, D. C.
1998. Endemic bird areas of the world : Priorities for
biodiversity conservation. BirdLife
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1981. Veld and
Pasture Management in South Africa. Shuter
and Shooter in Association with Natal University Press.
Pietermaritzburg. 26-56. Tainton N M and M T Mentis.
1984. Fire in Grassland. . In : Booysen P de V and Tainton (eds.). Ecological effects of fire in South African Ecosystems. Ecological Studies 48. Springer-Verlag.
Berlin. 115-147. Van der Zel D W. 1989. Strategic Forestry Development Plan for South Africa. Mimeographed Publication. Directorate of National Forestry Planning, Department of Environment Affairs. Pretoria.
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